enEnglisch
PP pipe systems, fittings and valves
Polypropylene (PP) has a higher heat resistance than PE and is therefore a favorable standard material for use at higher temperatures.
Furthermore, it is characterized by high mechanical strength, good chemical resistance and physiological harmlessness.
Our product range (PP pipes and fittings) includes different types of polymers: The homopolymers (PP-H), which are composed exclusively of propylene molecules, and the two different copolymers in which ethylene monomers are incorporated in blocks (polypropylene block copolymer, PP-B) or randomly distributed (polypropylene random copolymer, PP-R). Our pipes are made of PP-H and our fittings of PP-R as standard. Both types are highly heat stabilized and ideally suited for the production of piping systems subject to pressure. The various types of propylene can be joined using all common welding methods.
Impact strength is temperature-dependent and increases with rising temperature or decreases with falling temperature. PP-R has better impact strength than PP-H.
General properties of PP:
- high heat aging resistance
- high creep strength
- low density of 0.91 g/cm3
- temperature resistance from 0 °C to 95 °C (depending on the type of stress)
- good chemical resistance
- physiologically harmless + very good weldability
- resistance to microorganisms
- very good abrasion properties
- no deposits / no overgrowth
- PP is not permanently UV-resistant
Application examples:
PP homopolymers
- PP pipes for industrial applications
- Semi-finished products for container constructions
PP random copolymers
- Piping systems for high pressure and temperature loads (service water systems)
- for the food industry as PP "nature
- injection-molded parts
Delivery program:
- PP pipes
- short PP fittings
- long PP fittings
- PP electrofusion couplers
- PP fittings for socket welding
- PP valves
- PP semi-finished products
- PP welding wire
Advantages of using PP pipes and fittings:
- cost-effective installation due to the use of electrofusion, butt welding and socket welding
- poor heat conductor, therefore thermal insulation can often be dispensed
- very good weldability
- easy processing
- wide range of pipes and fittings available
Pressure table in bar for PP-H according to DIN 8077 with a safety factor of 1.25
| Temperature | SDR 11 | SDR 17,6 |
|---|---|---|
| 20 °C | 12,5 | 7,5 |
| 40 °C | 10 | 6,0 |
| 60 °C | 7,5 | 4,5 |
Behavior of PP when exposed to radiation
Polypropylene is generally not permanently resistant to high-energy radiation. The impact of high-energy radiation to polypropylene may result in a temporary increase in strength due to crosslinking of the molecular structure. However, permanent exposure to radiation causes the molecular chains to break, resulting in a considerable reduction in strength due to damage to the material. This behavior must be taken into account by a reduction factor, which must be determined experimentally.
Behavior of PP under UV radiation
Pipes made of grey polypropylene are not UV-stabilized and must therefore be protected accordingly. If effective protection is not possible, outdoor use is still possible in accordance with DVS 2210-1. Under UV radiation, an oxide layer forms on the pipe surface, which can be absorbed by a calculated wall thickness surcharge. According to DVS, this wall thickness surcharge should be at least 2 mm. The service life is limited to 10 years.
Physiological safety of PP
The composition of polypropylene complies with the relevant food regulations (according to BGA and KTW guidelines). Furthermore, PP pipes and fittings have been tested and approved for drinking water suitability.
Chemical resistance of PP
In principle, PP is considered resistant to a wide range of acids and alkalis. Alkaline solutions, phosphoric acid, hydrochloric acid are only a few of the substances to which PP is resistant. PP, on the other hand, is only conditionally resistant to hydrocarbons, as it can lead to swelling of >3%. As a result, PP is less suitable against gasoline. The same applies to free chlorine and ozone. Due to its high temperature resistance, PP is considered ideal for use in pickling plants, the chemical industry as well as highly aggressive wastewater. However, the chemical resistance must always be considered in conjunction with the operating temperature, operating pressure and any external stresses, as these may result in limitations. The chemical resistance list is intended as a first indication. Specific applications can be clarified with our technical department.
We are happy to advise you